Asahi Kogaku Kogyo Kabushiki Kaisha

Toa Nenryo Kogyo Kabushiki Kaisha

Toa Nenryo Kogyo, K. K.

Tao Nenryo Kogyo Kabushiki Kaisha

Keiko Fukamachi

Nobuaki Tagaya

Takao Hashimoto

Noriko Komatsu

Tsugio Maeshima

Hideyuki Kuwahara

Tetsuro Ogawa

Toshihiro Ishikawa

Masao Yoshizawa

Tsugio Maejima

Kimio Tamai

Hideyuki Kuwakara

Tetsuo Kanakubo

A calcium-phosphate type hydroxyapatite for chromatographic separation is in the form of spherulites having a mean particle diameter of 0.5 to 50 .mu.m, preferably 1 to 10 .mu.m. The spherulites are each an aggregate mainly of acicular crystallites belonging to a series of hexagonal systems and having unit lattice constants of 9.58.+-.0.08 .ANG. for the a axis and 7.00.+-.0.05 .ANG. for the c axis. The hydroxyapatite is produced by granulating a calcium=phosphate type hydroxyapatite in the form of a gel and then firing the granular apatite at 400.degree. to 700.degree. C., preferably at 500.degree. to 600.degree. C. The firing is performed by heating the granules in the presence of oxygen or air for a given period of time.

Calcium-phosphate type hydroxyapatite

A calcium-phosphate type hydroxyapatite for chromatographic separation is in the form of spherulites having a mean particle diameter of 0.5 to 50 .mu.m, preferably 1 to 10 .mu.m. The spherulites are each an aggregate mainly of acicular crystallites belonging to a series of hexagonal systems and having unit lattice constants of 9.58.+-.0.08 .ANG. for the a axis and 7.00.+-.0.05 .ANG. for the c axis. The hydroxyapatite is produced by granulating a calcium-phosphate type hydroxyapatite in the form of a gel and then firing the granular apatite at 400.degree. to 700.degree. C., preferably at 500.degree. to 600.degree. C. The firing is performed by heating the granules in the presence of oxygen or air for a given period of time.

Calcium-phosphate type hydroxyapatite for chromatographic separation and

An assemblage of hydroxyl apatite particles having small and uniform particle size. The median of the particle size is 1 to 10 .mu.m, and at least 90% of the particles in the assemblage have a particle size of not more than 25 .mu.m. The assemblage can be used to pack a liquid chromatography column.

Assemblage of hydroxyl apatite particles and liquid chromatography

A calcium-phosphate type hydroxyapatite which belongs to a series of hexagonal systems has unit lattice constants of 9.58.+-.0.08 .ANG. for the a axis and 7.00.+-.0.05 .ANG. for the c axis. Its Ca/P ratio is in the range of 1.50 to 1.90. It is for use as a column packing material for chromatographic separation of biopolymers. The hydroxyapatite is produced by firing it in the form of a gel or powder at a temperature of 400.degree. to 700.degree. C. As a gel the hydroxyapatite takes the form of a suspension or slurry. A powder is prepared by removing moisture from the hydroxyapatite in the gel form and then drying. Either gel or powder is fired by heating in the presence of oxygen or air at 500.degree. to 600.degree.0 C.

Calcium-phosphate type hydroxyapatite and process for producing same

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Keiko Fukamachi